Richard hammill



(No Model.) R. HAMMILL.

LADDER.

No. 426,180. Patented Apr. 22. 1890.

irn TATES ATENT OFFICE.

RICHARD HAMMILL, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE HAMMILL FIREESCAPE COMPANY, OF SAME PLACE.

LADDER.

SPECIFICATION forming part of Letters Patent No. 426,180, dated April22, 1890.

Application filed January 7,18 88.

To aZZ whom, it may concern:

Be it known that I, RICHARD HAMMILL, a citizen of the United States ofAmerica, residing at Chicago, in the county of Cook and State ofIllinois, have invented certain new and useful Improvements in Ladders,of which the following is a specification, reference being had thereinto the accompanying drawings.

IO This invention relates to ladders such as are adapted to be used inconnection with buildings to effect a ready means of ingress and egressin time of fire or emergency of any nature.

The object of the invention is to provide a ladder that will be strongand durable, and which will be light and economical in its e011-struction and easily put together, and which will be self-sustaining,requiring no braces of any nature other than the rungs, which will behereinafter more fully described and claimed, and shown in the annexeddrawings, in which Figure 1 is a front view, parts being broken away, ofa section of ladder embodying my invention; and Fig. 2, a cross-sectionof the ladder, showing a plan view of the rungs, the clamping-arms beingshown extended by dotted lines.

The risers A A may be of an length, size, and form" in cross-section,and may be solid or tubular, the latter being preferable because of thelightness and strength of a tubular riser, and because ordinary gas andwater pipes may be used.

The rungs B of cast metal have a broad head or cap D, which extends theentire length of the rung, and which is slightly curved on its uppersurface in cross-section,

the said surface being roughened to prevent any accidental displacementor slipping of the foot. The vertical rib or fin (Z on the under side ofeach of the rungs strengthens them and admits of the cap-plate D beingmade exceedingly thin and light. The vertical extensions a at each endof the rungs have their outer sides parallel and adapted to fit againstthe risers throughout their length. These extensions a taper from theirlower to their upper ends, which ends have clamping-armsc c, that areadapted to be bent about and embrace the risersA A. The

Serial No. 260,073. (No model.)

'bent to embrace the risers.

It will be observed that the vertical extensions a bear against therisers throughout their length. This is of vital importance, as itprevents any vertical movement of the risers and obviates the necessityof braces to steady them.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is

1. As an improved article of manufacture, the hereinbefore shown anddescribed malleable cast-metal rung for ladders, composed of thecapplate D, roughened and curved on its upper surface in cross-section,the vertical fin or rib (Z, the vertical extensions (1. at its endshaving their outer sides parallel and adapted to bear against the risersthroughout their length, the clamping-arms c c at the upper ends of theextensions aand the lugs I) at a lowerlevel than the arms 0 c,substantantially as and for the purpose described.

2. The herein shown and described ladder, composed of the risers havingopenings in the sides at intervals and the malleable cast-metal rungs,each composed of the thin cap-plate D, roughened and curved 011 itsupper surface in cross-section, the vertical rib or fin (Z, the verticalextensions to, tapering from bottom to top and bearing against the sidesof the risers throughout their length, the clampingarms c c, bent aboutthe risers, and the lugs b at a lower level than the said clamping arms,substantially as and for the purpose described.

In testimony whereof I afiix my signature in presence of two witnesses.

RICHARD IIAMMILL.

Witnesses:

H. W. SMEAL, E. E. MoRRtLL.

